New Tetradentate Acidic Catalyst for Solvent-Free Synthesis of 1-Amidoalkyl-2-Naphthols and 4,4′-(Arylmethylene)-Bis(3-Methyl-1-Phenyl-1H-Pyrazol-5-ol)s

In this work, a tetradentate acidic catalyst based on pentaerythritol tetrabromide and methylimidazole was designed and synthesized. The catalyst was characterized by Fourier transform infrared, H-1 NMR, C-13 NMR, and thermogravimetric analysis and its catalytic activity in the synthesis of 1-amidoalkyl-2-naphthols (from 2-naphthol, aryl aldehydes, and amide) and 4,4 '-(arylmethylene)-bis(3-methyl-1-phenyl-1H-pyrazole-5-ol)s (from aryl aldehydes, phenylhydrazine, and ethyl acetoacetate), two important classes of compounds, was investigated. The catalyst has multiple interesting properties such as hydrogen bonding interactions, high catalytic activity, heterogeneous feature, and ability to be useful under solvent-free condition.